FreeBSD3DD6CCF4-A3C6-11E7-A52E-0800279F2FF8OpenVPN -- out-of-bounds write in legacy key-method 1
CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:N/AC:M/Au:N/C:P/I:P/A:P
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
Percentile
80.5%
Steffan Karger reports:
The bounds check in read_key() was performed after using the value,
instead of before. If ‘key-method 1’ is used, this allowed an
attacker to send a malformed packet to trigger a stack buffer
overflow. […]
Note that ‘key-method 1’ has been replaced by ‘key method 2’ as the
default in OpenVPN 2.0 (released on 2005-04-17), and explicitly
deprecated in 2.4 and marked for removal in 2.5. This should limit
the amount of users impacted by this issue.
Related
CVSS2
Attack Vector
NETWORK
Attack Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:N/AC:M/Au:N/C:P/I:P/A:P
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
Percentile
80.5%